Allow proper highlighting on universal overflow scroll.

Source/core/rendering/RenderLayerScrollableArea.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 381 matching lines @@
     frame->eventHandler().dispatchFakeMouseMoveEventSoonInQuad(quadForFakeMouseMoveEvent);
 
     bool requiresRepaint = true;
 
     if (box().view()->compositor()->inCompositingMode()) {
         // Hits in virtual/gpu/fast/canvas/canvas-scroll-path-into-view.html.
         DisableCompositingQueryAsserts disabler;
         bool onlyScrolledCompositedLayers = scrollsOverflow()
             && !layer()->hasVisibleNonLayerContent()
             && !layer()->hasNonCompositedChild()
-            && !layer()->hasBlockSelectionGapBounds()
+            && layer()->hasBlockSelectionGapBounds() == RenderLayer::LayerDoesNotHaveBlockSelectionGaps
             && !box().isMarquee();
 
         if (usesCompositedScrolling() || onlyScrolledCompositedLayers)
             requiresRepaint = false;
     }
 
     // Just schedule a full repaint of our object.
     if (requiresRepaint) {
         if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled()) {
             if (box().frameView()->isInPerformLayout())
@@ skipping 1077 matching lines @@
     DisableCompositingQueryAsserts disabler;
     return box().hasCompositedLayerMapping() && box().compositedLayerMapping()->scrollingLayer();
 }
 
 bool RenderLayerScrollableArea::needsCompositedScrolling() const
 {
     return scrollsOverflow() && box().view()->compositor()->acceleratedCompositingForOverflowScrollEnabled();
 }
 
 } // Namespace WebCore